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Badger is a simple Rails plugin that creates photo badges. A site often allows its users to upload a profile image. A profile image is just that, an image resized to fit in a predefined space to show up in the user’s profile.

With Badger, you can have something prettier – a badge that shows the user- uploaded image on top of another image that identifies the user as a part of the community. We have company badges, security badges, so why not web badges to have your users show off his/her affection for your site?

Badger works by accepting cropping parameters of the overlay image in a hash (x1, y1, width, height), which is used to crop the overlay image. It then resizes the cropped image to the size specified by composite_width and composite_height in badger.yml. Finally, it places the resized image on top of the background image at location specified by composite_x and composite_y in badger.yml. The resulting image is saved back to either the filesystem or Amazon S3, using attachment_fu.

Badger requires the attachment_fu plugin, ImageMagick, and MiniMagick. Also, the JavaScript Image Cropper UI can be used to obtain the cropping parameters from the users.

Configuration

When this plugin is installed , the badger.yml will be copied to the config directory. You need to specify the following:

1. background : filename of the background image, searching from public/images
2. composite_x : top left corner of the overlay image location in x
3. composite_y : top left corner of the overlay image location in y
4. composite_width : width of the overlay image in pixels
5. composite_height : height of the overlay image in pixels

For example, I want to overlay an image on top of a background image (badge.jpg). The box for the overlay image should be 30 pixels in width and 20 pixels in height, and it should appear at (x, y) = (60, 80) of the background image. My badger.yml then looks like:

  development:
    background: badge.jpg
    composite_x: 60
    composite_y: 80
    composite_width: 30
    composite_height: 20

Example

In the model that you use to store attachments:

  class Photo < ActiveRecord::Base
    has_attachment :content_type => :image,
                   :storage => :s3,
                   :max_size => 1.megabytes,
                   :resize_to => '320x200>',
                   :thumbnails => { :thumb => '100x100>' },
                   :processor => :MiniMagick
    validates_as_attachment
    has_badge :storage => :s3
  end

In the controller:

  def create_my_awesome_badge
    @photo = Photo.find(params[:id])
    # params[:crop_coord] is a hash with indexes x1, y1, width, height
    @photo.create_badge(params[:crop_coord])
  end

Improvements Needed

Please feel free to submit patches for bug fixes and improvements. Specifically, I would like to:

1. Use something nicer than system(“convert blah…”), but couldn’t get it to work. I don’t think Minimagick supports compositing images, so RMagick may have to be used, but is it worth the heavy memory consumption?

2. Make it more flexible (i.e. accept background image and composite params dynamically instead of in badger.yml). Maybe pass them in the call to create_badge?

There have been several methods to deploy an Ruby on Rails application. Until recently, the most popular is to run Apache and proxy balance to multiple Mongrel instances that are running simultaneously.

Passenger, developed by Phusion, is the new kid entering the Rails deployment market. Everyone has been using the Apache PHP module for years and deploying a PHP applications is a snap. This has not been possible with Rails until Passenger. It is extremely easy, and you can still use Capistrano to automate deployment. I will show you how I get it to work on Ubuntu.

sudo gem install passenger
passenger-install-apache2-module

Update: Phusion just released Passenger 2.0 RC 1. You can download this version and do gem install passenger-1.9.0.gem instead. But I had an error compiling it on Mac OS X Leopard. hongli pointed me to use the version from GitHub that has the fix and it works like a charm. Thanks Phusion guys.

To get it from GitHub:

git clone git://github.com/FooBarWidget/passenger.git

I created a separate /etc/apache2/mods-available/passenger.load and it contains the following:

For 1.0.5:

LoadModule passenger_module /usr/local/lib/ruby/gems/1.8/gems/passenger-1.0.5/ext/apache2/mod_passenger.so
RailsSpawnServer /usr/local/lib/ruby/gems/1.8/gems/passenger-1.0.5/bin/passenger-spawn-server
RailsRuby /usr/local/bin/ruby

For the GitHub version (Of course the path will look different depending on where your git clone is):

LoadModule passenger_module /home/rlaw/downloads/passenger/ext/apache2/mod_passenger.so
PassengerRoot /home/rlaw/downloads/passenger
PassengerRuby /usr/local/bin/ruby

I then tell Apache to load the Passenger module:

a2enmod passenger

Now, I create a virtual host configuration for one of my Rails app in /etc/apache2/sites-available/myapp:

<VirtualHost *:80>
  ServerAdmin webmaster@myapp.com
  ServerName myapp.com

  DocumentRoot /home/deploy/apps/myapp/current/public

  <Directory /home/deploy/apps/myapp/current/public>
    Options FollowSymLinks
    AllowOverride None
    Order allow,deny
    Allow from all
  </Directory>

  LogLevel warn
  ErrorLog /var/log/apache2/myapp/error.log
  CustomLog /var/log/apache2/myapp/access.log combined
</VirtualHost>

I then restart Apache:

sudo /etc/init.d/apache2 reload

When you need to restart your application because you have changed some code that Rails does not reload in production, just do:

touch /home/deploy/apps/myapp/current/tmp/restart.txt

I have not tried their Ruby Enterprise Edition yet. They claim substantial memory and speed improvement at RailsConf 2008, so it will be interesting to see how that develops.